Clamping tape

ABSTRACT

A multilamina tape in which a first lamina has the property of substantial contraction and a second lamina attached thereto has the property of negligible contraction resulting in a coiling of the tape during contraction of the first lamina. The first lamina may be heat-, chemical- or radiation shrinkable. A preferred embodiment employs a linearly prestretched thermoplastic with a memory for its normal configuration to which it shrinks upon being activated to reach its plastic state with heat. The second lamina is formable thereby assuming a coiled configuration and may be serrated to provide a controlled direction of coil, ease of coiling due to increased flexibility in the direction of coiling and transverse rigidity perpendicular to the direction of coiling. Adhesive-heat, solvent or pressure activated-on the innermost surface of the coiled configuration serves to bond the coil to itself and to items contained thereby to form a permanent wrap or tie.

United States Patent [72] Inventor Paul .1. Glasgow Woodmere, N.Y.

[2 1] Appl. No. 749,215

[22] Filed July 31, 1968 [45] Patented Nov. 16, 1971 [7 3] AssigneeGlasgow Products, Inc.

Woodmen, N.Y.

[54] CLAMPING TAPE 12 Claims, 14 Drawing Figs.

[56] References Cited UNITED STATES PATENTS 2,138,568 11/1938Brandenberger 156/84 X 2,299,988 10/1942 Irving 156/85 2,942,300 6/1960Masters 161/214 UX Primary Examiner-William A. Powell Attorney-Stoll andStoll ABSTRACT: A multilamina tape in which a first lamina has theproperty of substantial contraction and a second lamina attached theretohas the property of negligible contraction resulting in a coiling of thetape during contraction of the first lamina. The first lamina may beheat-, chemicalor radiation shrinkable. A preferred embodiment employs alinearly prcstretched thermoplastic with a memory for its normalconfiguration to which it shrinks upon being activated to reach itsplastic state with heat. The second lamina is formablc thereby assuminga coiled configuration and may be serrated to provide a controlleddirection of coil, ease of coiling due to in creased flexibility in thedirection of coiling and transverse rigidity perpendicular to thedirection of coiling. Adhesive- -heat, solvent or pressure activatedonthe innermost surface of the coiled configuration serves to bond thecoil to itself and to items contained thereby to form a permanent wrapor tie.

PATENTEDNUV 18 I97| 3,820,896

1111111111111 1111, III] [Ill/112a [N VE'N T 016 PAUL J- GLASGO W B; AMQJM ATTORNEYS CLAMPING TAPE BACKGROUND OF THE INVENTION 1 Field of theInvention Securing devices for securing wire and cable bundles and thelike.

2. Description of the Prior Art The necessity for joining together atfrequent intervals a varying group of parallel wires has grown with theadvent of sophisticated electrical and electronic devices. The moreinvolved the circuitry and the more sensitive the circuit components toesthetics, compactness, and field interactions, the greater has becomethis need for neat, easily formed harnesses.

The common means for joining wires into bundles in the past haveincluded rudimentary and laborious hand-tying with lacing cord, plasticstrap and buckle arrangements and adhesive tapes. To one extent oranother, each of the common means has required a manual looping of thestring, strap or adhesive tape around the wire bundle, a matter ofdifficulty particularly in close and delicate quarters.

SUMMARY OF THE INVENTION Accordingly, the present invention provides aclamping means for circumferentially clamping groups of objects, yetrequiring an operation from one side only. The clamping means of thepresent invention is self-adapting to varying shapes and sizes ofmembers to be clamped.

Briefly, and not by way of limitation, the present invention comprises atape having at least two laminae of different coefficients ofcontraction joined to prevent interlamina relative movement duringcontraction.

A first lamina has the property of extreme contraction in a preferentialdirection. The second formable lamina will not contract to anymeaningful degree. Contraction of the first causes coiling of thecomposite tape with the first lamina on the interior (smallest radius).The second lamina has serrations to provide rigidity parallel to theserrations and flexible formability normal to the serrations in thelamina plane.

Contraction of the first lamina is caused by selected application ofenergy sufficient to cause the first lamina to contract and transmit acompressive force on the inner fibers of the second lamina therebycausing both to assume a coiled configuration.

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a planview of a fragmentarylength of a two laminae clamping tape in accordance with the presentinvention.

FIG. IA is a cross-sectional view takenacross line lA-lA of FIG. 1 andshowing a first form of the invention in which the second lamina has acontinuous upper surface for joining to the first lamina.

FIG. 2 is a pictorial view of a group of wires held by a clamping tapein accordance with a second form of the present invention.

FIG. 3 is an enlarged cross-sectional view similar to that of FIG. IAbut of a second form of the invention in which the upper surface of thesecond lamina is serrated in sawtooth fashion.

FIG. 4 is a cross-sectional view taken across line 4-4 of FIG. 3 showingthe upper surface of the formable lamina of the second form of thepresent invention showing the direction of the compressive forcesimparted by the first, shrinkable, lamina.

FIG. 5 is a view similar to that of FIG. 4 showing the upper surface ofthe formable lamina of a third form of the present invention showing theoblique direction of the serrations and the oblique orientation of thecompressive forces upon contraction of the first lamina.

FIG. 6 is a pictorial view of a group of wires held by a clamping tapein accordance with a third form of the present invention.

FIG. 7 is a cross-sectional view similar to that of FIG. 3 but showing afourth form of the invention.

FIG. 8 is a cross-sectional view similar to that of FIG. 3 but showing afifth form of the invention.

FIG. 9 is a side view of the clamping tape of FIG. 8 in its clampingconfiguration.

FIG. 10 is an enlarged plan view of a fragmentary length of clampingtape in accordance with another form of the present invention.

FIG. I1 is a cross-sectional view taken across line I I ll of FIG. 10.

FIG. 12 is a cross-sectional view taken across line 12-12 of FIG. 11.

FIG. 13 is a side view of the clamping tape of FIG. 10 in its clampingconfiguration.

DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION Referring to thedrawing, the clamping tape 10 of the present invention is provided witha first, contractable lamina I2 and a second, formable, lamina 14 joinedthereto. In a first form of the invention, as shown in FIG. 3, there areno other operative laminae although various coatings may be applied forprotection, identification or adhesion.

Contractable lamina 12 has the property, whether an attribute of itsmaterial or an attribute of a previous operation, of rapid contractionunder controlled application of energy such as chemical radiation(particle or electromagnetic) or, preferably, thermal. Contraction isessentially linearly of the tape and transverse contraction should beminimal; it could be eliminated or minimized by a previous operation inpreparation of this material. An example of such a previous operation isto prestretch the material linearly in the presence of radiation.Examples of materials suitable to the preferred contraction by heat arefilms of Neoprene, Mylar, Teflon (all trademarks of E. I. duPont deNemours and Company, the first for a synthetic rubber, the second for apolyester and the third for a tetrafiuoroethylene), Penntube l and II(trademark of Pennsylvania Fluorocarbon Co. Inc. for a fluorinatedethylpropylene), Cryovac (trademark of W. R. Grace & Co. for apolyethylene and polypropolene composition) and Reynolon (a trademark ofReynolds Metal Co. for a preferentially oriented polyvinyl chloride).The application of controlled amounts of heat to the energy level ofmaterial plasticity but not to the point at which the material loses itsmemory for its prestretched dimensions will cause contractable lamina I2to contract, sometimes as much as 50 to 70 percent of its originalstretched dimensions.

Formable lamina 14 has the properties of relatively easy formation to aconfiguration which it holds without a memory of any prior configurationand of negligible contraction as compared to contractable lamina 12.Examples of materials suitable for formable lamina I4 are thin metals orsemirigid plastics such as vinyl, polyvinyl chloride, polypropylene,styrene, Neoprene, Lexan (a trademark of General Electric Company) andnylon.

Formable lamina 14 may be flat as shown in FIG. 1A or may be providedwith a serrated upper surface 14a in which the peaks of the serrationsdefine a substantially planar surface to which contractable lamina I2 ispermanently affixed. In the second form of the present invention asshown in FIG. 4, the serrations are transverse of the tape longitude; inthe third form of the invention as shown in FIG. 5, the serrations runat an oblique angle from the transverse. The serrations provide arigidity in a direction parallel to each serration, and a flexibility ina direction perpendicular to each serration, both directions being inthe plane of formable lamina I4. The preferred direction of contractionof lamina I2 is properly oriented to always contract perpendicular tothe serrations. Accordingly, there is controlled curving or loopingduring contraction of contractable lamina 12. In the second form of theinvention tape I0 is caused to loop spirally about itself as shown inFlG. 2 and extended lengths of the tape will continue to spiral in everincreasing radii with the tape encircling itself repeatedly untilexhausted. ln the third form of the invention the tape will loophelically as shown in FIG. 6 rather than assume the spiral of the secondform. Extended lengths of the third form of the tape will form a helixsubstantially coaxial with the members (wires in FIG. 6) to be joined.Top surface of lamina 12 is coated with an adhesive, chemical or thermalactivation of which causes it to bond to the surfaces it contacts afterthe looping has occurred thereby forming a permanent wrap.

Both the second and third forms of the invention are shown to haveserrations on upper surface 140 of formable lamina 14 only. In the fifthform of the invention as shown in FIG. 8, formable lamina 14 is shown tohave its serrations constitute the entire formable lamina which istherefore sharply corrugated. Such full serrations may run transverse ofthe tape longitude or angularly with respect thereto; in the coiledshowing of the fifth form of the invention in FIG. 9 it is clear thattransverse corrugations'have produced the spiral. The form of theinvention shown in FIG. 10 utilizes a contractable lamina 12 which isnarrower than formable lamina l4 and which rests in a central channelformed in upper surface 14a between shoulders or side serrations 14cwhich rise slightly above surface 14a. Bottom surface 14b of formablelamina 14 is also serrated. With transverse serrations this form of theinvention will form a spiral coil as shown in H0. 13. The overlappingportions of the spiral will tend to engage each other to preventslipping, lower serrations 14b being exposed to secure shoulders 140.

The fourth form of the invention shown in FIG. 7 is substantiallysimilar to the preceding forms of the invention, having contractablelamina 12 and formable lamina 14. Additionally, the fourth form of theinvention is provided with a third lamina having the general propertiesof the formable (second) lamina but with an even smaller rate ofcontraction.

Joining of the various laminae may be such means as adhesives, rivets,or welding of the impact, ultrasonic or solvent varieties.

While the foregoing is illustrative of preferred embodiments and formsof the invention, it is clear and other forms and embodiments may be hadwithin the broad teaching of the disclosure and the broad scope of theappended claims. For example, the third lamina has been shown in FIG. 7to be a bottom layer to the preceding forms of the invention. Clearly,the third lamina may be applied to the fifth form of the invention inFIG. 8 and thereby present a smooth lower surface.

What is claimed is:

l. A multilamina tape, comprising:

a. at least two strips which are laminated together,

b. one of said strips being linearly contractable relative to the otherstrip,

c. to impress a curved form upon both strips,

d. said other strip being provided with a continuum of parallelserrations,

e. to control the direction of curvature of said tape.

2. A multilamina tape in accordance with claim 1, wherein a. saidcontinuum of parallel serrations are disposed transversely of the tapelongitude.

3. A multilamina tape in accordance with claim 1, wherein:

a. said continuum of parallel serrations arc angularly disposed withrespect to the tape longitude.

4. A multilamina tape in accordance with claim I, wherein:

a. the uppermost portions of the serrations continuum defines asubstantially planar surface to which the linearly contractable strip isjoined,

b. to prevent interlamina movement.

5. A multilamina tape in accordance with claim 4, wherein:

a. said laminae are joined by ultrasonic welding.

6. A multilamina tape in accordance with claim 4, wherein:

a. said laminae are joined by solvent welding.

7. A multilamina tape in accordance with claim 4, wherein:

a. said laminae are joined by impact welding.

8. A multil amina tape in accordance with claim 4, wherein: a. saidlaminae are oined by riveting.

9. A multilamina tape in accordance with claim 1, wherein:

a. the voids formed by said continuum of serrations are filled with anadhesive,

b. which is squeezed from said voids upon coiling of said tape to coatadjacent surfaces.

10. A multilamina tape in accordance with claim 9,

wherein:

a. said adhesive is thermally activated. 11. A multilamina tape inaccordance with claim 9, wherein:

a. said adhesive is air-setting.

12. A multilamina tape, comprising:

a. at least two strips which are laminated together,

b. one of said strips being linearly contractable relative to the otherstrip,

c. to impress a curved form upon both strips,

d. said other strip being provided with a serrated exposed surface,

e. to provide locking teeth which prevent a coil from opening.

2. A multilamina tape in accordance with claim 1, wherein a. saidcontinuum of parallel serrations are disposed transversely of the tapelongitude.
 3. A multilamina tape in accordance with claim 1, wherein: a.said continuum of parallel serrations are angularly disposed withrespect to the tape longitude.
 4. A multilamina tape in accordance withclaim 1, wherein: a. the uppermost portions of the serrations continuumdefines a substantially planar surface to which the linearlycontractable strip is joined, b. to prevent interlamina movement.
 5. Amultilamina tape in accordance with claim 4, wherein: a. said laminaeare joined by ultrasonic welding.
 6. A multilamina tape in accordancewith claim 4, wherein: a. said laminae are joined by solvent welding. 7.A multilamina tape in accordance with claim 4, wherein: a. said laminaeare joined by impact welding.
 8. A multilamina tape in accordance withclaim 4, wherein: a. said laminae are joined by riveting.
 9. Amultilamina tape in accordance with claim 1, wherein: a. the voidsformed by said continuum of serrations are filled with an adhesive, b.which is squeezed from said voids upon coiling of said tape to coatadjacent surfaces.
 10. A multilamina tape in accordance with claim 9,wherein: a. said adhesive is thermally activated.
 11. A multilamina tapein accordance with claim 9, wherein: a. said adhesive is air-setting.12. A multilamina tape, comprising: a. at least two strips which arelaminated together, b. one of said strips being linearly contractablerelative to the other strip, c. to impress a curved form upon bothstrips, d. said other strip being provided with a serrated exposedsurface, e. to provide locking teeth which prevent a coil from opening.